Litter box assembly



FIG. 1 is a left, front perspective view of a litter box assembly shown according to the present design;

FIG. 2 is a front end view thereof;

FIG. 3 is a rear end view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines illustrate portions of the litter box assembly and form no part of the claimed design. 

CLAIM The ornamental design for a litter box assembly, as shown and described. 